The sensory processing and perception of visual information requires the transmission of neural activity across a multisynaptic pathway from striate cortex, or area 17, through several prestriate "association areas." In addition, visual input from striate cortex reaches these prestriate areas via two subcortical visual structures, the superior colliculus and the pulvinar. We have begun to explore the complex circuitry and visuotopic organization of these connections in the primate visual system by the combined use of anterograde degeneration and autoradiographic tracing techniques. Future experiments will examine efferents of prestriate projection areas to determine the pathways by which visual information is relayed from the occipital lobe to visual areas located within the parietal and temporal lobes.